Barrel type injection pump



April 28, 1953 w. H. MASHINTER BARREL TYPE INJECTION PUMP 8 Sheets-Sheet 1 Filed Dec. 8, 1948 April 28, 1953 w. H. MASHINTER BARREL TYPE INJECTION PUMP 8 Sheets-Sheet 2 Filed Dec. 8. 1948 WZZzZzm JNVENIOR.

April 28, 1953 w. H. MASHINTER 2,636,439 BARREL TYPE INJECTION PUMP Filed Dec. 8, 1948 8 Sheets-Sheet 5 INVENTOR.

April 1953 w. H. MASHINTER 2,636,439

BARREL TYPE INJECTION PUMP F iled Dec. 8, 1948 a Sheets-Sheet 4 Apiil 1 w. H. MASHINTER 2,636,439

BARREL TYPE INJECTION PUMP Filed Dec. 8. 1948 8 Sheets-Sheet 5 INVENTOR.

April 28, 1953 w; MASHINTER BARREL TYPE INJECTION PUMP 8 Sheets-Sheet 6 Filed Dec. 8. 1948 INVENTOR April 28, 1953 w. H. MASHINTER BARREL TYPE INJECTION PUMP 8 Sheets-Sheet '7 Filed Dec. 8, 1948 INVENTOR. H/Vaakazfen Patented Apr. 28, 1953 BARREL TYPE INJECTION PUMP William H. Mashinter, Chicago, 111., assignor of nineteen per cent to Margery D. McCormick and Alan G. McCormick, both of Chicago, Ill.

Application December 8, 1948, Serial No. 64,076

21 Claims 1 This invention pertains to a fuel injection system for an engine, and particularly to a system embodying a fuel injection pump, a transfer pump for supplying fuel from a source of supply to the fuel pump, air .throttling means, and fuel supply control means associated with the fuel pump and throttling means for supplying the proper ratio of combustibles (air and fuel) to the associated engine.

Fuel injectors are substantially universally employed withlow-speed oil engines of the diesel or semi-diesel type as a means for introducing thereto the heavier grade of liquid fuels such as are commonly used in engines of that type. But the lighter fuels employed, the higher operating speeds, and the wider range of speeds and loads required of gasoline engines present fuel injection problems that heretofore have never been satisfactorily solved. v

An object of the present invention is to provide a fuel injector particularly adapted for use with engines of the high-speed type, employing lighter grades of fuel such as gasoline.

Another object of the invention is to provide a fuel injector so organized as to produce a fully developed readily combustible fuel spray within the very minute interval of time available at high operating speeds.

Another object of the present invention is to provide a substantially leak-proof fuel injection pump.

Another object of the invention isto provide a fuel injection pump that is substantially immune to leakage producing wear.

Another object of the invention is to provide an improved diaphragm type of pump capable of withstanding high pressures over long periods of use.

Another object of the invention is to provide a mixture ratio control mechanism for injectors. Another object of the invention is to provide automatic em'iching mechanism and automatic leaning mechanism for injectors.

Another object of the invention is to provide pump mechanism so constructed and arranged that it may be used to pump solid liquid.

Another object of the invention is to provide a pump for supplying fluid under pressure and in measured quantities to means for utilizing the supplied fluid, as where fuel is sprayed into the cylinder of an engine or where other liquid, such as water, is sprayed into such cylinder for power or anti-detonating reasons.

Another object of the invention is to provide injecting means for supplying fuel to an internal combustion engine which may be used with manifold or separate cylinder injection and wherein the fuel is introduced in properly atomized con- 'dition over the entire range of operation .of the engine, i. e., regardless of theoperating speedof the engine.

Another object of the invention is to provide an injector for supplying fuel to an internal combustion engine, wherein a balanced diaphragm is 1 used as the fuel pumping means.

Another object of the invention is to provide injecting means wherein the amount of fluid supplied therefrom is controlled by the pressure of the fluid delivered to the injecting means.

Another object of the invention is to provide a fuel injector adapted particularly for use with engines of a high speed type, whether operating on heavy, intermediate, or light grade fuels.

Another object of the invention is to provide an injector so constructed and arranged that it is not dependent upon any particular shape of actuating cam; but shapes of cams may be resorted to as desirecL to obtain a suitable variation of injector output with variations in injector speed of operation (engine speed).

Another object of the invention is to provide ,an injector so constructed that it will operate over a large range of supply pressures.

Another object of the invention is to provide a fuel injector so constructed and arranged that av complete degree of load-speed control is obtained by virtue of four independent controls over theamount of fuel emitted per injection, that is, (1 mechanical throttle, (2) variable supply pressure,l(3) speed of injection operation,

and (4) manifold-pressure.

Another objectof the invention is to provide ,an injector using a controlled balanced diaphragm form of pump means for injection operation. p

Another object is to provide a fuel injector :capable of effecting a more accurate control of the quantity of fuel injected throughout theentire range of engine speeds and loads.

Another object of the invention is to provide-a fuel injection system wherein no special air release mechanism need be provided to eliminateaccidentally entrapped air, as the system is so designed as to digest such entrapped air without damage to the operation thereof.

Another object of the invention is to provide a system wherein there are no frictionally moving parts in that portion of the fuel handling means through which the fuel passes.

Another object of the invention is to provide a transfer pump for an injection system wherein the amount of the fuel delivered is controlled (or maintained) by a preset relief valve on the pumping fluid side which controls the pressure applied to the fuel.

Another object of the invention is to provide a transfer pump for an injection system wherein the amount of fuel supplied can automatically be preselected according to the demand.

Another object of the invention is to provide a transfer pump for an injection system wherein fuel is supplied at substantially constant pressure (substantially without pulsations).

Another object of the invention is to provide a transfer pump for an injection system wherein the driving force for the fuel is yieldable, and adjustable means (spring), which is energized by positively operable means (cam), is adapted to be driven by the engine to which the fuel is ultimately supplied, or by any other power means.

Another object of the invention is to provide a transfer pump for an injection system wherein the transfer pump embodies all the objects herein enumerated for the injection pump.

With these and various other objects in view,

the invention consists of certain novel features of construction and operation as will be more fully described and particularly pointed out in the specification, drawings and claims appended hereto.

In the drawings, which illustrate embodiments of the device and wherein like reference characters are used to designate like parts'- Figure 1 is a fragmentary, sectional elevation of an internal combustion engine provided. with If an injection system embodying the invention;

Figure 2 is a sectional elevation through. the injection pump of the system illustrated inv Figure 1, the same showing in detail an injection pump assembly embodying the invention;

Figure 3 is a transverse, sectional plan view taken substantially in the plane as indicated by the line 3-3 of Figure 2;

Figure 4 is a transverse, sectional plan view taken substantially in the plane as indicated by the line 3-4 of Figure 2;

Figure 5 is a transverse, sectional plan View taken substantially in the plane as indicated by the lines 5-5 of Figures 1 and 2 and showing both the pump and air to fuel ratio control device;

Figure 6 is a transverse, sectional plan view taken substantially in the plane as indicated by the line 6-6 of Figure 2;

Figure 7 is a transverse, sectional plan view taken substantially in the plane as indicated by the line 'I-1 of Figure 2;

v Figure 8 is a bottom plan view of the injection pump illustrated in Figure 2;

Figure 9 is a side elevation of the plate cam for operating the pumping assemblies of the inject o p p;

Figure 10 is a sectional elevation of a roller follower assembly used in the pumping assemblies;

Figure 11 is a bottom plan view of the roller follower assembly illustrated in Figure 10;

Figure 12 is a front elevation of the throttle finger of the injection pump, the same looking toward the left as viewed in Figure 2;

Figure 13 is an enlarged sectional elevation of -the plunger throttle yoke of the injection pump Figure 15 is a top plan view of the plunger illustrated in Figure 14;

Figure 16 is an enlarged sectional elevation of a diaphragm stop member utilized in a pumping assembly, the same being taken substantially in the plane as indicated by the line l6-I6 of Figure 17;

Figure 17 is a bottom plan view of the stop member illustrated in Figure 16;

Figure 18 is a transverse sectional elevation of the diaphragm assembly used in a pumping assembly;

Figure 19 is a transverse sectional elevation of the transfer pump used in the system illustrated in Figure 1, the section being taken substantially in the plane as indicated by the line 19-19 of Figure 20;

Figure 20 is a top plan view of the transfer pump illustrated in Figure 19, with the cover thereof removed;

Figure 21 isa bottom plan view of the transfer pump illustrated in Figures 19 and 20;

Figure 22 (sheet. 1 of the drawings) is a fragmentary elevation of a modified form of connection between the transfer pump and source of fuel supply of the system shown in Figure l, and

Figure 23 is a fragmentary, sectional top plan view, more or less diagrammatic, showing mechanical means for operating the injector pump and air throttle valve, the same looking down on the butterfly valve illustrated in Figure 1', the sec- .tion of the pump being taken substantially in the plane as indicated by the line 55 of Figures 1 and Zr Referring first of all, more particularly, to the injection system illustrated in Figure 1, the internal combustion engine is-provided witha certain number of cylinders, in the embodiment shown, the engine being a six cylinder one. The cylinders are each provided with reciprocating pistons, properly timed and fired, with respect to each other, and by way of example the single cylinder 52 shown in block 54 is provided with reciprocating piston 55, the engine being provided with cylinder head 58 Said head 58 is provided with a combustion chamber above each cylinder, such as combustion chamber 60 provided above cylinder 52.

Cylinder head 58 is provided with theair inlet or throttle housing 62 open at one endjto the atmosphere, preferably through a suitable air cleaner (not shown) ,the housing being provided with throttle lever E l connected through shaft to butterfly valve 68. Movement of throttle lever fi l between the full and dotted linefipositions illustrated in Figure 1 determines the quantity of air supplied through the throttle housing, it being noted that valve 58 is never quite closed.

Throttle housing 62 communicates with manifold "it, connected through suitable 7 air ports or passages to the combustion chambers, cylinder air port if: being illustrated connecting manifold it to the combustion chamber 86. Flow through port it is controlled by valve M adapted to be moved between open and closed positions on seat 15, the valve stem 18 extending through a suitable guide 8!! and being actuated by means such as rod and rocker arms (not shown) overhead cams or the like, the cams controlling valve "it, and similar valves to the other cylinders bein operated by a suitable cam shaft (or cams) timed with respect to the operation of the pistons ('56 and the like) of the engine, in the wellknown manner.

Manifold l'il communicates, through port. 82,

incense with one end-f the pipe 84, the other end of said pipe being connected through port 88 (Figured) to the chamber 88 of air tofuel ratio control device 85. Chamber 83 is defined by cap (it and flexible diaphragm e2 fastened between cap Sit and housing member M, atmosphere chamber 96 defined between diaphragm 92 and housing 94 communicating with the atmosphere through port 98. Diaphragm 92 is urged toward the left as viewed in Figure 5 by the spring loll, one end of said spring being seated on the spring seat I02 provided on the diaphragm, the opposite end of said spring being received in helical grooves HM, of adjustable spring retainer Hi6.

Retainer act is provided with threaded adjusting extension Hill provided with tool (screw driver) receiving recess lit, extension "33 being threaded to threaded retaining sleeve H2, said sleeve being suitably shouldered as at ll l to engage complementary shoulders on housing so; A sealing retaining washer H6 is interposed betweenhousing 9i! and closure nut H8 whereby when the nut is tightly in place a sealing function occurs between sleeve l 52, housing as and washer HE, whereby chamber 86 is closed to atmosphere thereby only having communication with manifold It (Figure 1).

Diaphragm as is provided with nut urn (Figure 5) threadedly connected to complementary threads of pump throttle rod 122, said throttle rodextending into guide passage 524 of housing 126 provided on injection pump housing I28, the stroke. of throttle rod 22 being governed by adjusting screw 529 extending into passage I24. Throttle rod IE2 is connected through slot It!) to ball i352 (forming a ball and slot connection) provided on pin ltd, said pin being as at I38 to throttle finger collector ring i3 8 (Figures Za'nd .5). Pin tilt carried by the collector ring,

is fixed to the ring by assembling it radially outwardly of the ring and is tightly secured to the ring by abutting the shank of the pin against shoulder ltd provided on the collector ring.

The injection pump (Figures 1-48) is providedlwith cam drive shaft Hi2 shown as mounted in antifriction bearings hi l and I 45 (Figures 2 and 3), said shaft being driven, preferably by the engine at a certain speed, for example at half crank shaft speed for a four stroke cycle engine and at crank shaft speed for a two stroke cycle engine. Bearing i l l is suitably mounted in the barrel housing M8 adjacent the pump base and valve housing 558, housing M8 being suitably secured as at 455 to housing i511 (Figures 2, 7 and 8) Antifriction bearing Mt is mounted in upper bearing housing I52, forming part of the pump housing and to as at Hit, the inner race bearing Hill being plate cam {56, secured to shaft M2 .to be rotated thereby. Cam r56 is provided with lobe l5'8 adapted to contact rollers I68 (Figures 2, 4 and pivotally mounted as by pins I (52 provided on each cam or roller follower assembly 656. The axes of pins E52 intersect the axis of cam drive shaft M2 to properly present rollers to the cam lobe lfill as it rotates to engage said rollers.

In the construction illustrated, the engine illustrated in Figure 1, is assumed to be a six cylinder engine. Consequently the injection pump is provided with six pumping assemblies illustrated generally in Figures 4 and 6 at 268, I10, I12, I74, I16 and H8. Inasmuch as all of the pumping assemblies are similar, a description closed by closure I53 secured thereof said antifriction' mounted on journal lli l'of to arms 564,

of only one pumping-assembly, such as illustrated in Figure 2, need be made in detail.

Cam follower assembly 566 (Figures 2 and 10) is provided with a substantially cylindrical p01:- ticn or skirt I80, slotted as at I82, for the purpose to be later described, and end closure I84, of the roller follower assembly is provided with spaced apertures I86. Cylindrical skirt $86 of the follower assembly is, adapted to reciprocate in cyl inders or bores Nil (Figures 2 and 4) provided in follower-housin 988, said bores accommodating assemblies I65 to I78, inclusive, respectively, the follower assemblies being lubricated through passage Ilid (Figure 2,).

Follower housing I88 is provided with pin I98 (Figure 2) adapted to be received in slot. m2 of the follower assembly I66 to prevent rotation of said follower assembly and to maintain the axes of: pins It? in the before mentioned positions, housing I88 being secured to barrel housing M8 by studs lllIv (Figures 4 and 6), and secured to housing member I52 as by studs 93" (Figures 2, 3, 4, 5 and 23). Thus lobe I58 of cam I56 will always engage rollers I in proper path, for U while the assemblies its and rollers Illa may reciprocate. they cannot rotate about'the axes of bores l8'i.

Upper spring seat I 92' (Figure 2-) is provided within cylindrical member E80, being seated thereon as at Hit, and one end of spring I96 seats on said seat I92, the other end of said spring seating upon lower spring seat member I98, which in turn seats upon shoulder Elli) formed in bores it? of follower housing I88. Upper spring seat, I92 is provided with a reces 252 for the reception of the head 2M (Figures 2, 14 and 15') provided on the upper stem portion 285 (Figure is) of metering plunger 2%, lower end portion Ell? of said plunger being provided with the helical metering or cut-off edge or portion 208.

Collector ring 138 is provided with elongated slots 2 ill, sixin number in the embodiment shown", and in substantial radial alignment (Figure 5) with pumping assemblies N58 to H8, inclusive. Throttle fingers 2l2 (Figures 2 and 12) are adjustably connected to collector ring i325 through slots 2H3, as by means of the cap screws 2 threadedly connected to complementary threads in fingers ZIZ. Fingers 2I2 extend downwardly of pump housing I28, fingers 2l2 being oscillatably mounted on spaced tracks M8 on housing I88 whereby freedom of rotation of finger 212 (about the axis of shaft I42) is obtained. Fingers 212 are provided with shoulder 218 supported on the corresponding shoulder on the follower housing I88.

The lower end of the fingers are bifurcated as at 2228 (Figures '2 and 12) for receiving theball end 222 of the plunger throttle yoke 224 (Figures 2 and 13). The yoke is provided'with the oil cular segmental portion 225 which in turn is slotted as at for embracing the fiat shank portion 230 (Figures 14 and 15) of the metering plunger 265'. The segmental portion 2% is supported on the upper rim of the barrel retaining nut 232 (Figure 2) and is rotatably (and hor zontally as viewed in Figure 2) positioned by the circular recess 234 provided in lower spring seat i313. Thus plunger throttle'yoke 224 is positioned in ahorizontal plane and is permitted slldable engagement with metering plunger lltd'the flat portion 236 of the plunger being long enough to permit the full allowable stroke of the plunger, rotation of yoke 224 by the associated throttle finger 2| 2 causing rotation of the plunger and 7 consequently a change in position of the hell'ca edge or portion 208.

Retaining nut 232 (Figure 2) is provided with hex head 236 to facilitate the application of nut 232 into barrel housing I48, nut 232 being provided with threads 238 adapted to have threaded engagement with complementary threads provided in housing I48, nut 232 having spaced passages 239 permitting passage of liquid. Plunger 206 reciprocates in barrel 246, said barrel extending within nut 232, shoulders 242 relatively positioning the barrel and nut, and said barrel seats at its lower end on diaphragm stop member 244 (Figures 2, 16 and 1'7). Barrel 240 is provided with slot 246 adapted to receive one end of barrel set screw 248, whereby said barrel is fixed against rotation, and said barrel is provided with ports 25!! communicating with the inside of said barrel and controlled by plunger 206 reciprocating therein.

Stop member 244 (Figures 2, 16 and 1'7) is provided with passage 252 which communicates with upper port 254, which in turn communicates with barrel 240"below plunger 206. Said passage 252 also communicates through ports 256 with the cavity or recess 256 (Figure 16) which is provided between wall 260 of stop member 244 and the top of resilient diaphragm 262 (Figures 2 and 18). In other words, wall 260 is disposed above or recessed within the outer rim 263 of Stop member 244. Diaphragm 262 is preferably made of a flexible, resilient material which is chemically inert to petroleum products or to the product being pumped, and the hydraulic fluid, such as synthetic rubber; plastics as Teflon (tetrafluoro ethylene), methyl acrylate, or metals as 18-8 stainless steel, said diaphragm being bonded or otherwise held to a diaphragm ring 264 (Figure 18) which is of flanged construction, the lower inwardly directed flange 265 (Figure 18) being seated on a shoulder 266 (Figure 2) provided on valve housing I50 in alignment with each pumping assembly and being fixed by engagement with rim 263 of stop member 244.

Flange 265 extends inwardly to a fuel cavity 268 3 provided in housing I50, to a point where it covers the spaced ports 210 and 212.

Inlet port 210 (Figure 2) is adapted to be supplied with fuel by means of inlet valve 214, spring 216 interposed between the valve and housing I50 urging the valve to seated position on the'seat of valve seat member 213 which is held in place in valve housing 150 by nut 230. -Access to nut 280 is readily had through closure screw 28! disposed in housing 150 in alignment-with the adjusting nut 280. Ihe valve stem of valve 216 is provided with flats or grooves for permitting passage of liquid past the stem and to port 210 when the valve is open, nut 280 being ported as at 232 for permitting passage of fuel to the valve. Fuel intakemanifold 284 (Figures 1, 2 and 8) is provided on pump base housing I50, and is provided with inlet fitting 286(Figures 1 and 8) and fuel outlet 288 connected respectively to lines 290 and 292 (Figure 1). Line 200 is connected to outlet 294 (Figures 19 and 21) of transfer or supply pump 236, and line 292 is a return to fuel storage tank 298 (Figure 1). With the transfer pump such as illustrated in Figures 19 to 21, inclusive, return line 292 is not always necessary, so either no outlet fitting is provided, or it is plugged up and may be used for flushing the pump under certain conditions.

Port 212 (Figure 2) communicates with outlet valve 300 seated on seat member 302 provided in a suitable recess disposed in valve housing I50, the valve stem of valve 300 beinglikewise provided with flats or grooves for ermitting the passage of fuel thereby, the valve being urged toward closed position by means of spring 304 interposed between said valve 300 and a suitable valve seat provided in outlet fitting 306. Fitting 306 is suitably connected to line or pipe 308 (Figure 1) which is, in turn, connected to nozzle 310 suitably secured to the engine to supply fuel into combustion chamber 60, nozzle 310 being preferably of the construction shown and described in application Serial No. 617,752, filed September 21, 1945, Mashinter and Gilbert, Spray Nozzle, now Patent No. 2,555,803. In the construction shown, there will, of course, be six outlet fittings 306 (Figure 8) from each of the pumping assembliss 58-413, each connected through its line 308 to the respective nozzle 3I0 of the associated cylinder.

Transfer pump 236 (Figures 1, 19, 20 and 21) is provided with the transfer pump drive shaft 3% preferably driven as by the cam shaft of the engine, the volume pumped by the pump being in excess of the fuel requirements of the system. Drive shaft 312 is provided with cams 3|4 and 316 and said shaft is adapted to rotate in a counterclockwise direction as viewed in Figure 19. Bell cranks 343 and 320 are oscillatably mounted on the shaft 322 disposed adjacent and parallel to shaft 3i2. Cams 3M and 3l6 and bell cranks (H8 and 320 are adapted to operate a pair of similar pumping assemblies 324 and 326 (so that it is only necessary to describe one assembly) two or more pumping assemblies preferably being used to eliminate supply pulsations.

Shaft 332 is suitably journaled in, and shaft 322 is disposed in, upper housing 323 which is closed by covers 330 and 332 (Figures 19 and 20) and housing 326 is provided with lower housing 334 suitably secured to the upper housing. Housing 328 is threaded as at 335 (Figure 19) for the reception of upper spring seat 336 for the upper end of compression spring 340, the lower end of said spring being seated on spring seat 342 carried on shoulder 344 provided on plunger shank 346.

Plunger shank 346 is headed as at 348, the head contacting over substantially a line contact with antifriction member 350 disposed between head 343 and bifurcated arm 352 of bell crank 320 (and 3|8). The lower end or piston (or plunger) 354 of the plunger is adapted to re-- ciprocate in bore 356 provided in lower housing 334, and communication is had from chamber 358 of upper housing 323, through passage 360, passage 362 and port 364 to chamber 366 above diaphragm stop member 363. The diaphragm stop member is held between the shoulder 310 and diaphragm ring 3'62 positioned on shoulder 314 of lower housing member 316 of lower housing 334.

Diaphragm stop member 368 (Figure 19) is similar to diaphragm stop member 244 (Figure 16), being provided with port 313 communicating with chamber 366, said port communicating with transverse passage 380 communicating with ports 382 and 364. Ring 3'52 is provided with diaphragm 386, of similar material to diaphragm 262, and is suitably held to the ring 312. Below diaphragm 386 and ring 312 a fuel cavity 388 is provided, communicating through inlet port 390 with inlet 392 (Figures 19 and 21) which is connected through inlet pipe or line 394 (Figure 1) to supply tank 298.

.9. Intake valve retaining screw 396 (Figure 19) is secured in bore 388 of member 3%, the lower end of said bore being closed by closure 400, screw 396 being provided with passage H32 ther through, said screw forming positioning means for intake valve 4M. Said valve comprises a ported valve seat and retaining member 486 and valve disk its urged towards closed position by means of spring m whereby the passage from inlet 392 to 100113399 is controlled. Cavity 'Bliil is'c'onnected through'port M2 to outlet 294, said outlet communicating with bore did closed at its lower endby the closures t, a ported spring seat M8 being threadedly secured withinsaid bore said spring seat positioning the ported valve seat member 42d. Said valve seat member d2 secured between an upper shoulder or rim spring seat member H8 and a shoulder onlower housing member 376 adjacent port H12. Valve 222 is adapted to seat on seat member Mil, being urged towards closed position .by means of spring 42 3 interposed between seat member tilt and valve 422, the valve stem being provided vwith flats for permitting passage .of fuel fromsaid port M2, "past valve 422. and through the port of spring seat i 38 to outlet 2S4. Outlet 2% communicates with passage 426 (Figure 21) and inlet 392 communicates with passage 32%, said passages zcominunicating'with the intake and outlet valves of both pumping assemblies of transfer pump 2%, and both passages being closed-at one endas'by plugs 63%.

.In .orderito balance the pressure on diaphrag: .s

262 (Figurez) and .386 (Figure.19), and to provide lubrication for the parts of barrel pump (Figure 2) and transfer pump (Figures 19., 20 and '21), barrel or injection pump hydraulic oil is placedin casing l28 (Figure 2') filling it to the level indicated at 532 (Figure 2) from the diaphragrns, and transfer pump hydraulic oil .is placed in transfer pump 2% filling the casing to the level we (Figure 19) from the diaphragms, i. e., enough oil is provided to provide an adequate splash system and insure oil being between the pistons and associated diaphragms. 1 lnFigure '22 (Sheet .1) there is shown a'modification of the return line connection-.shownin Figure 1. In Figure 22 return line 292 is provided with check valve 436 opening toward the source of supply 298, the valve beingset to open at a .pressure'below that of supply pump 29%; so that any air trapped between pump 2%, manifold 28 i and valve e36 will be eliminated.

In the operation of the system and the parts thereof illustrated in Figures 1 to 22, inclusive, it is assumed that engine 54 is a six cylinder, four "stroke cycle engine, firing in the conventional manner (as l, 5, 3, 6, 2, 4) and wherein transfer pump drive shaft 3122 is conveniently operated as from the cam shaftuor crank shaft of the engine, though of course it is to be understood that the transfer pump may be operated by any power driven means. The transfer pump is driven so that it supplies more fuel to the barrel pump (Figure 2) than is'necessary to operate the bar-rel pump at maximum capacity, thus insuring that diaphragms 212 of the barrel pump never bottom, and: engine .54 is always supplied with enough fuel.

Drive shaft 12 of the injection pump is convenientlydriven by (four stroke cycle) engine '54 at one-half crank shaft speed as before described. -Where a two stroke cycler'engine is used, shaft 1421s driven at crank shaft-speed. Rotation of shaft 312 a counterclockwise direction,- as

viewed in Figure 19, causes cam 3| 6 (and cam 3M) to rotate, oscillating bell crank .320 in a clockwise direction as viewed in Figure 19, lifting plunger shank 346 to compress spring 34.0. Upward movement of plunger 1346 causes upward movement of piston d in the transfer pump hydraulic oil.

It will be seen that downward movement of the plunger is dependent upon spring .340, and not upon the direct drive from camtlfi. Expansion of spring 340 causes downward movement of piston 351i, which in turn causes thelhydraulic oil between piston 35% and diaphragm 386 to flow through passengers 318, 380 and ports 382 to depress diaphragm 386 downwardly into fuel cavity 385. Any fuel in cavity 388 will be displaced, causingsaid fuel to flow through port 412, past valve 422, being supplied through passage 426 (Figure 21) and port 2% to line .290, through which it is supplied to the inlet 236 (Figures 1 and 8) of the injection pump.

When fuel from cavity 388 has ceased to flow past valve 422 (and when the pressure of the hydraulic oil above diaphragm 386 is relieved by piston'35'4 being raised) spring 424 will close said valve. Inasmuch as cams 3H5 and 3M are disposed apart, while one piston 1354 is moving downwardly on its supply stroke, the other piston isbeing raised. As cam 314 (or 3 I6) is operating the bell crank 318 (or 3'29) to raise thepassociated piston 354, the other piston is being moved on its compression stroke. Upward movement of piston 354 will relieve the pressure of the transfer .pump hydraulic oil on diaphragm 386, previously compressed onjits supply stroke, permitting the-diaphragm to return to normal position, such as illustratedin Figure 19. Upwardmovemerit of -piston 354 tends to pull a vacuum, thus aidingthe return of diaphragm 386 to its normal position.

Inasmuch as the fuel has been displaced from cavity 338 on the discharge stroke, upward movement or return movement of the diaphragm will tend-to pull a vacuum in cavity 38.3, causing valve 408 to open against spring 4 I 0, and causing fuel to be drawn from tank 298 (Figure .1), through line .3 94, through port 392 and passage 428, past valve Mill and through-port 39b into-cavity 338 conditioning said cavity :to supply fuel .to discharge port .294 as hereinbefore described. Due to the fact that while oneof the plungers .354 is performing its compression .or supply stroke. the other plunger is performing its suction-stroke, there will always be an abundant supply of fuel through line 29b to the transfer pumpat constant pressure. Fuel which is constantly sup plied to linezild will be supplied through inlet-2.85 (Figures 1 and 8) to fuel intake manifold 284 (Figure 2), said manifold communicating with ports 282 of inlet valves 21A of the respective pumping assemblies.

vRotationof shaft 142 (Figure '2) will rotate cam i 56 causing lobe E58 of the cam to serially engage rollers is!) of the pumping assemblies. Lobe I 58 will cause downward movement ofro'lle'r follower assembly let of the pumping assemblies one after another, causing the cam follower-assembly to reciprocate in the injection pumpzhydraulic oil. Downward movement of cylindrical ,portion I80 will ,causespring' E96 to'be compressed andafter cylindrical member .180 has moved .a predetermined amount in a downward direction .(a few thousandths of an: inch in the embodimentshown) it will engage head .204 :Of plunger 1 l 206 to move the plunger downwardly with assembly I66.

Downward movement of plunger 206 will cause the injection pump hydraulic oil, disposed below the lower end of the plunger, to flow downwardly through port 254, passage 252 and ports 256 to act upon the top of diaphragm 262, causing downward deflection of diaphragm 262 into cavity 266. Fuel disposed in cavity 268 will be forced through port 2'12, past valve 300, which has been opened against spring 304, and through line 308 to the respective injection nozzle 3I6 through which it is supplied to the associated combustion chamber 60.

Movement of lobe I58 to disengage roller I60, of the actuated roller follower assembly, will permit spring I96 to move roller follower assembly I66 upwardly, and will also cause upper spring '7 seat I92 to pick up head 204 of plunger 266 to move it upwardly to a position where it is ready for another downward stroke, in which position the before mentioned clearance is between the top of head 264 and roller follower assembly I66. As above pointed out, cam I66, in its rotation, successively engages the roller of the follower assemblies, causing downward movements of the respective pistons of the pumping assemblies supplying fuel in the proper order and selected amount to the combustion chambers of engine 54, and the return of said pistons by the respective springs I96 will cause upward movement of the pistons permitting the pump pressure of transfer pump 296 to aid in returning diaphragms 262 to their normal dwell positions wherein they are disposed such as shown in Figure 2.

Return of said diaphragms to said dwell positions tends to cause a vacuum to be formed in cavities 268 and this, aided by the pressure supplied by transfer pump 266, will cause valves 274 to be opened against spring 216 to fill said cavities 268, inasmuch as immediately upon cessation of the supply of fuel past valves 300, said valves will close. The cavities thus filled will be conditioned for the next compression or supply (to engine) stroke.

As before pointed out, if transfer pump 296 supplies more fuel to manifold 284 than is actually needed by the injector pump, said fuel will return through line 292 to the source of supply. If return line 292 is not used, no more fuel will be supplied by the transfer pump to the injector pump than is actually needed by the injector pump for it to supply the proper amount of fuel through injectors 3 I to the respective combustion chambers, inasmuch as due to the construction of transfer pump 296, springs 340 (Figure 19) will only supply the amount of fuel to the injector pump that it is using.

The capacity of transfer pump 296 is preferably made large enough so that it is always capable of supplying more fuel to the injector pump than the injector pump will supply to nozzles 3I0, so that in the event air is trapped in the system, or the operation of the system is initiated when the injection pump is in dry condition or substantially dry condition, only a few revolutions of transfer pump shaft 3I2 is necessary to supply anadequate amount of fuel to the injector pump so that it can become operative to supply fuel to injectors 3I0 of engine 54.

In the construction illustrated in Figure 22 return line 292 is provided with check valve 436 opening toward source of supply 298, but set to open at a pressure below that of supply pump 296 so that valve 436 will openquickly and eliminate 12 any air trapped between transfer pump 296, manifold 264 and valve 436, thus eliminating air from being supplied to the injectors particularly upon initiation of the operation of the system.

Variations of the output of the engine are obtained by movement of butterfly valves 68 (Figure 1) by lever 64, which lever 64 may be connected to the conventional accelerator pedal or other actuator. In Figure l valve 68 is shown in full line position wherein it is nearly, but not quite closed, so that some air can be supplied to manifold I9, in which position of valve 66 engine 54 is in idling condition. In this idling condition the engine vacuum is generally between seventeen and twenty-one inches of mercury. The idling manifold vacuum acts upon diaphragm 92 (Figure 5) causing the diaphragm to move against spring I06 thereby moving throttle rod I22 toward the right as viewed in Figure 5, in turn causing throttle pin I34 to move collector ring I38 in a counterclockwise direction as viewed in Figure 5.

Movement of ring I38 in a counterclockwise direction causes throttle fingers 2I2 (Figures 2 and 12) to move yoke 226 (Figures 2 and 13) to rotate the metering plunger 206. Plunger 206 is rotated to a position where the plunger has an effective stroke sufficient to supply the idling quantity of fuel to the combustion chamber. In other words, the helix is so disposed that a sufficient quantity of oil is by-passed through ports (Figure 2) to only retain sufficient oil below the plunger to actuate diaphragm 262 an amount necessary to supply the idling quantity of fuel.

(In the embodiment shown, the idling position is not the position of the minimium deflection of diaphragm 262. Actually this deflection is more than this minimum deflection. By way of example, the system herein disclosed has been applied and successfully operated on a 572 cubic inch four stroke cycle, naturally aspirated, 6 cylinder engine wherein it is necessary to supply substantially cubic millimeters of fuel on the idle (substantially 350 R. P. M.) and substantially cubic millimeters at full throttle, and the injection pump can be controlled to supply only 4 cubic millimeters of fuel.)

In the idling position wherein the metering plunger is properly disposed, diaphragm 92 (Figure 5) is in the position where it is balanced by the spring I06, inasmuch as the spring is set by adjustable spring retainer I66 (Figure 5 to the proper position wherein the vacuum multiplied by the area of diaphragm 92 is equal to the pressure or resistance of spring I00.

With throttle valve 68 (Figure 1) closed to the predetermined position such as illustrated in the full line position of Figure 1 setting the throttle control is effected, that is, in order to set diaphragm 92 (Figure 5) to a position to give the selected air-to-fuel ratio, an adjustment is made at nut I20, whereas spring rate of the spring I00 is adjusted by means of retainer I66 and retaining sleeve II2.

Movement of throttle lever 64 from the full line position toward the dotted line position shown in Figure 1, causes valve 68 to move from its idling or nearly closed, position, toward the dotted line or maximum. open position. This opening of the throttle (and throttle valve 68) permits additional quantities of air to be introduced into manifold -10, thus changing the vacuum conditions in said manifold and consequently in chamber 88 (Figure. 5). This change is a lowering of the engine vacuum which causes accents spring lotto move diaphragm or toward the left as viewed in Figure 5, until the position of balance is reached. This movement causes throttle rod I22 to move toward the left as viewed in Figure 5, rotating ring ltd in a clockwise direction, which in turn moves throttle yokes 226 to rotate metering plungers Eds causing earlier registration of the helices with ports thus making more of the plunger stroke eiiect'ive, thereby increasing the amount of deflection of diaphragms 252.. As the deflection of diaphragms 262 become greater, more fuel is supplied from cavities 258 past valves tilt to the respective jeotor's are. The maximum position of ring I38, that is, the maximum amount or fuel supplied to the combustion chamber, is controlled by means or set screw 529 which controls the limit of movement or throttle rod 22 toward the left as viewed in Figure 5, thus controlling the limit of rotation of metering plungers ate.

. Assuming the load to be constant, as throttle valve I68 (Figure 1) is opened, more and more fuel will be supplied. through nozzle valves 3 16 and increased speed of rotation will be obtained by the crank shaft of engine 54.

Assuming that valve $8 is in a position in the engine above referred to, that at 2400 R. P. M. there is a 69% output, it the load is varied to decrease the engine speed, to, for example, 1600 RP. the vacuum conditions have, during that time, changed from 8%, inches to 5 inches and the fuel quantity supplied to each cylinder has varied from 123 cubic millimeters (at 2400 R. P. .M.) to substantially 14.8 cubic millimeters at 1 600 P. M), Device so, being an air-tofuel ratio control, as distinguished from merely a governor, will maintain the fixed aunt's-fuel ratio selected regardless of the speed or load conditions and regardless of the throttle positions.

The function or fuel ratio control device 529 is to maintain a selected air-to-iuel ratio at all times, regardless oi any combinations of speed and load. This is done by adjusting the spring return of spring lflil (Figure 5). Adjusting retainer we inwardly of housing or causes a less and less number of con'volutions of the spring to be effective in their operation in resisting the movement of diaphragm 92. The fewer the effective convolutions of spring we, the greater the manifold pressure change required for a given motion or throttle rod 122.

Thus once the manifold pressure conditions and their air how to the engine are known, adjustment of spring loll can be made to maintain at all times the selected air-to-fuel ratio under all conditions of operation.

Referring now to the control modification illustrated in Figure '23, pump 128 is similar to that illustrated in Figure '2 and is provided with collector ring 33 adjustably secured as at 214 to control lingers 212 (Figure 2), it being understood that pump 2'96, with or without connections 2:92 (Figures '1 and 22) is used. In fact the only inaior change in this Figure '23 over Figure 1 is the control. Pump shaft 142 is provided, as already described, having operating cam 156 thereon for the pumping assemblies (Figure 2). Collector ring 538 is provided with pin I 3 connected through ball 132 and slot 138 to pump throttle rod I22 slidably mounted in housing I28.

Red 1 22 is pivotally connected as at E38 to link 41!). Link can is adiustably connected through couplingct i to link EM, set screws MB and M8 securing links-44E and BM to coupling W2. Lin-k MM is pivotally, adjustably and slid;-

14 ably connected through the pin and-slot connection 456 to-throttle lever A52, similar to throttle 1ever.64.

Lever 452 is secured toshaft 654 of butterfly valve 456, said shaft being journalled in throttle housing 458, similar to housing 52. Shaft 454 is also adjustably secured as at ten to lever 462 which is ,pivotally and adjustably connected as at 464 to a suitable link 46% adapted to be connected to and operated by the usual foot or hand feed mechanism.

It will be seen that by operating link 4% valve 356 is operated simultaneously and to the same extent as at collector ring 133, and consequently the pumping assemblies shown in Figure 2., and already described.

In adjusting this mechanism, adjustment is made at 446, 4348, 459, 468 and 564. The ratio of fuel and air mass flow is adjusted for any engine to an optimum, by said adjustments, and these adjustments are locked to maintain this optimum, so that thereafter there is a proper relative operation between throttle valve Mill and the pumping assemblies.

It is to be understood that this application is not t be limited by the exact embodiments of the device shown, which are merely by way of illustration and not limitation as various and other forms 01" the device will, of course, be ap parent to those skilled in the art without departing from the spirit of the invention or the scope of the claims.

I claim:

l. A pumping device including a casing having pumping assemblies therein, a rotatable shaft having a cam thereon, each assembly comprising a reciprocating cam follower disposed in a cylindrical bore provided substantially equidistant from and radially of the axis of the shaft, said follower being adapted to be reciprocated by said cam, a lower spring seat member disposed in said bore, an upper spring seat member engaging said cam follower a spring interposed between said spring seat members and urging said cam follow or toward said cam, a flexible diaphragm disposed in said bore, a stop member disposed in said bore and fixing said diaphragm therein-said bore below said diaphragm having a wall forming a fuel cavity shaped to permit deflection of said diaphragm, said casing being provided with hydraulic fluid disposed therein above and to a predetermined level above said diaphragm, a barrel member fixed in said first named bore above said stop member and having a cylindrical barrel bore therein, isaid barrel member having a port to permit said hydraulic fluid to flow intosaid barrel bore, said stop vmember having a passage connectsai-d bar l bore to the first named bone between the member and diaphragm, a plunger mounted for reci 'araoation .in said barrel bore, the end of said plunger'in said barrel bore being cut away adjacent the'ports in said barrel member whereby position or cut away portion controls the amount or hydraulic fluid disposed between said and diaphragm and conse quently the amount of deflection of said diaphra'gm as said plunger moves toward said dim phragm, the other end of said plunger being con nected'to said upper sprin seat member, a throttle yoke disposed between said lower spring seat and barrel member and sl'idably embracing said plunger, rotation of said yoke causing rotation of said plunger to selectively position said out away portion of said plunger with respect to the barrel member port, an oscillatabie finger momher for rotating said yoke, a collector member connected to each finger member of each pumping assembly for rotating each yoke, a fuel intake manifold communicating with the fuel cavity, an inlet valve between said manifold and cavity, an outlet from said cavity, and an outlet valve between said cavity and outlet.

2. A pumping device including a casing having a pumping assembly therein, a movable cam, said assembly comprising a reciprocating cam follower disposed in a cylindrical bore provided substantially equidistant from and radially of the axis of the shaft, said follower being adapted to be reciprocated by said cam, a lower sprin seat member disposed in said bore, an upper spring seat member engaging said cam follower, a spring interposed between said sprin seat members and urging said cam follower toward said cam, a flexible diaphragm disposed in said bore, a stop member disposed in said bore and fixing said diaphragm therein, said bore below said diaphragm having a wall forming a fuel cavity shaped to permit deflection of said diaphragm, said casing being provided with hydraulic fluid disposed therein above and to a predetermined level above said diaphragm, a barrel member fixed in said first named bore above said stop member and having a cylindrical barrel bore therein, said barrel member having a port to permit said hydraulic fluid to flow into said barrel bore, said stop member having a passage connecting said barrel bore to the first named bore between the stop member and diaphragm, a plungermounted for reciprocation in said barrel bore, the end of said plunger in said barrel bore being cut away adjacent the ports in said barrel member whereby the position of said cut away portion controls the amount of hydraulic fluid disposed between said plunger and diaphragm and consequently the amount of deflection of said diaphragm a said plunger moves toward said diaphragm, the other end of said plunger being connected to said upper spring seat member, a throttle yoke disposed between said lower sprin seat and barrel member and slidably embracing said plunger, rotation of said yoke causing rotation of said plunger to selectively position said cut away portion of said plunger with respect to the barrel member port, an oscillatable finger member for rotating said yoke, means for oscillatin said finger member, a fuel inlet communicating with said fuel cavity, an inlet valve between said fuel inlet and cavity, an outlet from said cavity, and an outlet valve between said cavity and outlet.

3. A pumping device including a casing having pumping assemblies therein, a rotatable shaft having a cam thereon, each assembly comprising a reciprocating cam follower disposed in a cylindrical bore provided substantially equidistant from and radially of the axis of the shaft, said follower being adapted to be reciprocated by said cam, a lower spring seat member disposed in said bore, an upper spring seat member engaging said cam follower, a spring interposed between said spring seat members and urging said cam follower toward said cam, a flexible diaphragm disposed in said bore, a stop member disposed in said bore and fixing said diaphragm therein, said bore below said diaphragm having a wall forming a fuel cavity shaped to permit deflection of said diaphragm, said casing being provided with hydraulic fluid disposed therein above and to a predetermined level above said diaphragm, a barrel member fixed in said first named bore above said stop member and having a cylindrical barrel bore therein, said barrel member having a port to permit said hydraulic fluid to flow into said barrel bore, said stop member having a passage connecting said barrel bore to the first named bore between the stop member and diaphragm, a plunger mounted for reciprocation in said barrel bore, the end of said plunger in said barrel bore being cut away adjacent the ports in said barrel member whereby the position of said cut away portion controls the amount of hydraulic fluid disposed between said plunger and diaphragm and consequently the amount of deflection of said diaphragm as said plunger moves toward said diaphragm, the other end of said plunger being connected to said upper spring seat member, the connection between said plunger and upper spring seat including a head provided on said plunger disposed between said upper spring seat and cam follower and of less thickness than the space between said cam follower and upper spring seat whereby there is a small lost motion between said plunger and upper spring seat and cam follower, a throttle yoke disposed between said lower spring seat and barrel member and slidably embracing said plunger, rotation of said yoke causing rotation of said plunger to selectively position said cut away portion of said plunger with respect to the barrel member port, an oscillatable finger member for rotating said yoke, a collector member connected to each finger member of each pumping assembly for rotating each yoke, a fuel intake manifold communicating with the fuel cavity, an inlet valve between said manifold and cavity, an outlet from said cavity, and an outlet valve between said cavity and outlet.

' 4. A pumping device including a casing having a pumping assembly therein, a variable cam, said assembly comprising a reciprocating cam follower disposed in a cylindrical bore provided substantially equidistant from and radially of the axis of the shaft, said follower being adapted to be reoiprocated by said earn, a lower spring seat member disposed in said bore, an upper spring seat member engaging said cam follower, a spring interposed between said spring seat members and urging said cam follower toward said cam, a flexible diaphragm disposed in said bore, a stop member disposed in saidbore and fixing said diaphragm therein, said bore below said diaphragm having a wall forming a fuel cavity shaped to permit deflection of said diaphragm, said casing being provided with hydraulic fluid disposed therein above and to a predetermined level above said diaphragm, a barrel member fixed in said first named bore above said stop member and having a cylindrical barrel bore therein, said barrel member having a port to permit said hydraulic fluid to flow into said barrel bore, said stop member having a passage connecting said barrel bore to the first named bore between the stop member and diaphragm, a plunger mounted for reciprocation in saidzbarrel bore, the end or said plunger in said barrel bore being cut away adjacent the ports in said barrel member whereby the position of said cut away portion controls the amount of hydraulic fluid disposed between said plunger and diaphragm and consequently the amount of deflection of said diaphragm as said plunger moves toward said diaphragm, the other end of said plunger being connected to said upper spring seat member, the connection between said plunger and upper spring seat including a head provided on said plunger disposed between said upper spring seat and cam follower and of less thickness than the space between said cam follower and upper spring seat whereby there is a small lost motion between said plunger and upper spring seat and cam follower, a throttle yoke disposed between said lower spring seat and barrel member and slidably embracing said plunger, rotation of said yoke causing rotation of said plunger to selectively position said cut away portion of said plunger with respect to the barrel member port, an oscillatable finger member for rotating said yoke, means for oscillating said finger member, a fuel inlet communicating with said fuel cavity, an inlet valve between said fuel inlet and cavity, an outlet from said cavity, and an outlet valve between said cavity and outlet.

5. A pumping device including a casing having pumping assemblies therein, a rotatable shaft having a cam thereon, each assembly comprising a bore in said casing disposed substantially equidistant from and radially of the axis'of said shaft, a fiexible diaphragm disposed in said bore,'a stop member disposed in said bore adjacent said diaphragm, said bore below said diaphragm having a wall forming a fuel cavity shaped to permit deflection of said diaphragm, said casing being provided with hydraulic fluid disposed therein above and to a predetermined level above said diaphragm, a barrel member fixed in said bore above said stop member and having a cylindrical barrel bore therein, said barrel member having a port to permit said hydraulic fluid to flow into said barrel bore, said stop member having a passage connecting said barrel bore to the first named bore between the stop member and diaphragm, a plunger mounted for reciprocation in said barrel bore, the end of said plunger in said barrel bore being cut away adjacent the port in said barrel member whereby the position of said cut away portion controls the amount of hydraulic fluid disposed between said plunger and diaphragm, and consequently the amount of deflection of said diaphragm as said plunger moves toward said diaphragm, the other end of said plunger being provided with means resiliently urging said plunger to follow said cam whereby said plunger is reciprocated in accordance with the movement of said cam, a throttle yoke slidably embracing said plunger, rotation of said yoke causing rotation of said plunger to selectively position the cut away portion of said plunger with respect to the barrel member port, an oscillatable finger member for rotating said yoke, a collector member connected to each finger member of each pumping assembly for rotating each yoke, a fuel intake manifold communicating with the fuel cavity, an inlet valve between said manifold and cavity, an outlet from said cavity, and an outlet valve between said cavity and outlet.

6. -A pumping device including a casing having pumping assemblies therein, a cam movable in said casing, each assembly comprising a bore in said casing, a flexible diaphragm disposed in' said bore, said bore below said diaphragm having a wall forming a fuel cavity shaped to permit deflection of said diaphragm, said casing being provided with hydraulic fluid disposed therein above and to a predetermined level above said diaphragm, a barrel member fixed in said bore above said diaphragm and having a cylindrical barrel bore therein, said barrel member having a port to permit said hydraulic fluid to flowinto said barrel bore, said barrel bore communicating with said first named bore above said diaphragm, a plunger mounted for reciprocation in said barrel bore. the

end of said plunger in said barrel bore being cut away adjacent the port in said barrel member whereby the position of said cut away portion controls the amount of hydraulic fluid disposed between said plunger and diaphragm, and consequently the amount of deflection of said diaphragm as said plunger moves toward said diaphragm, the other end of said plunger being provided with means resiliently urging said plunger to follow said cam whereby said plunger is reciprocated in accordance with the movement of said cam, means for rotating said'plunger, a collector member connected to each of said last named means of each pumping assembly for rotating each plunger, a fuel inlet communicating with the fuel cavity, an inlet valve between said inlet and cavity, an outlet from said cavity, and an outlet valve between said cavity and outlet.

'7. A pumping device including a casing having pumping assemblies therein, a cam movable in said casing, each assembly comprising a bore in said casing, a flexible diaphragm disposed in said bore, said bore below said diaphragm having a wall forming a fuel cavity shaped to permit deflection of said diaphragm, said casing being provided with hydraulic fluid disposed therein above and to a predetermined level above said diaphragm, a barrel member fixed in said bore above said diaphragm, and having a cylindrical barrel bore therein, said barrel member having a port to permit said hydraulic fluid to flow into said barrel bore, said barrel bore communicating with the first named bore above said diaphragm, a plunger having an end mounted for reciprocation in said barrel bore, the other end of said plunger being provided with means resiliently urging said plunger to follow said cam whereby said plunger is reciprooated by said cam, means for moving said plunger whereby said plunger controls the port to vary the amount of hydraulic fluid disposed between said plunger and diaphragm, and consequently the amount of deflection of said diaphragm as said plunger moves toward said diaphragm, a collector member connected to each of said last named means of each pumping assembly for controlling each of said last named means, a fuel inlet communicating with the fuel cavity, an inlet valve between said inlet and cavity, an outlet from said cavity, and an outlet valve between said cavity and outlet. Y

8. A pumping device including a casing having a pumping assembly therein, a movable cam, said assembly comprising a bore in said casing, a flexible diaphragm disposed insaid bore, said bore below said diaphragm having a wall forming a fuel cavity shaped to permit deflection of said diaphragm, said casing being provided with hydraulic fluid disposed therein above and to a predetermined level above said diaphragm, a barrel member fixed in said bore above said diaphragm and having a cylindrical barrel bore therein, said barrel member having a port to permit said hydraulic fluid to flow into said barrel bore, said barrel bore communicating with the first named bore above said diaphragm, a plunger mounted for reciprocation in said barrel bore, the end of said plunger in said barrel bore being cut away adjacent the port in said barrel member whereby the position of said cut away portion controls the amount of hydraulic fluid disposed between said plunger and diaphragm, and consequently the amount of deflection of said diaphragm as said plunger moves toward said diaphragm, the other'end of said plunger being provided with means resiliently urging said plunger to follow said cam whereby said plunger is reciprocated in accordance with the movement of said cam, means for rotatin said plunger, a fuel inlet communicating with said fuel cavity, an inlet valve between said fuel inlet and cavity, an outlet from said cavity, and an outlet valve between said cavity and outlet.

9. A pumping device including a casing having a. pumping assembly therein, a movable cam, said assembly comprising a bore in said casing, a flexible diaphragm disposed in said bore, said bore below said diaphragm having a wall forming a fuel cavity shaped to permit deflection of said diaphragm, said casing being provided with bydraulic fluid disposed therein above and to a predeterminedlevel above said diaphragm, a barrel member fixed in said bore above said diaphragm and having a cylindrical barrel bore therein, said barrel member having a port to permit said hydraulic fluid to flow into said barrel bore, said barrel bore communicating with the first named bore above said diaphragm, a plunger having an end mounted for reciprocation in said barrel bore, the other end of said plunger being provided with means resiliently urging said plunger to follow said cam whereby said plunger is reciprocated by said cam, means for moving said plunger whereby said plunger controls the port to vary the amount of hydraulic fluid disposed between said plunger and diaphragm, and consequently the amount of deflection of said diaphragm as said plunger moves toward said diaphragm, a fuel inlet communicating with said fuel cavity, an inlet valve between said fuel inlet and cavity, an outlet from said cavity, and an outlet valve between said cavity and outlet.

10. A pumping device including a casing having pumping assemblies therein, a cam movable in said casing, each assembly comprising a bore in said casing, a flexible diaphragm disposed in said bore, said bore below said diaphragm having a wall forming a fuel cavity shaped to permit deflection of said diaphragm, said casing being provided with hydraulic fluid disposed therein above and to a predetermined level above said diaphragm, a barrel member fixed in said bore above said diaphragm and having a cylindrical barrel bore therein, said barrel member having a port to permit said hydraulic fluid to flow into said barrel bore, said barrel bore communicating with the first named bore above said diaphragm, a plunger having an end mounted for reciprocation in said barrel bore, the other end of said plunger being actuated by the cam whereby the plunger is reciprocate by said cam, means operable to cause the plunger to selectably variably control said port to vary the amount of hydraulic fluid disposed between said plunger and diaphragm, and consequently the amount of deflection of said diaphragm as said plunger moves toward said diaphragm, a fuel inlet communicating with said fuel cavity, an inlet valve between said fuel inlet and cavity, an outlet from said cavity, and an outlet valve between said cavity and outlet.

11. A pumping device including a casing having pumping assemblies therein, a cam movable in said casing, each assembly comprising a bore in said casing, a flexible diaphragm disposed in said bore, said bore below said diaphragm having a wall forming a fuel cavity shaped to permit deflection of said diaphragm, said: casing beingprovided with hydraulic fluid disposed therein above and to a predetermined level above said diaphragm, a barrel member fixed in said, bore above said diaphragm and having a cylindrical barrel bore therein, said barrel member having a port to permit said hydraulic fluid to flow into said barrel bore, said barrel bore communi. eating with the first named bore above said diaphragm, a plunger having an end mounted for reciprocation in said barrel bore, the other end of said plunger being actuated by the cam whereby the plunger is reciprocated by said cam, means operable to cause the plunger to selectably variably control said port to vary the amount of hydraulic fluid disposed between said plunger and diaphragm, and consequently the amount of deiiection of said diaphragm as said plunger moves toward said diaphragm, a collector member connected to each of said last named means of each pumping assembly for controlling each of said last named means, a fuel inlet communicatin with the fuel cavity, an inlet valve between said inlet cavity, an outlet from said cavity, and an outlet valve between said cavity and outlet.

12. A pumping device including a casing having pumping assemblies therein, a cam movable in said casing, each assembly comprising a bore in said casing, a flexible diaphragm disposed in said bore, said bore below said diaphragm having a wall forming a fuel cavity shaped to permit deflection of said diaphragm, said casing above said iaphragm being adapted to be provided with a predetermined amount of hydraulic fluid, a barrel member fixed in said bore above said diaphragm and having a cylindrical barrel bore therein, said barrel member having a port to permit said hydraulic fluid to flow into said barrel bore, said barrel bore communicating with the first named bore above said diaphragm, a plunger having an end mounted for reciprocation in said barrel bore, the other end of said plunger being actuated by the cam whereby the plunger is reciprocated by said cam, means operable to cause the plunger to selectably variably control said port to vary the amount of hydraulic fluid disposed between said plunger and diaphragm, and consequently the amount of deflection of said diaphragm as said plunger moves toward said diaphragm, a fuel inlet communicating with said fuel cavity, and inlet valve between said fuel inlet and cavity, an outlet from said cavity,. andv an outlet valve between said cavity and outlet.

13. A pumping device including a casing having a pumping assembly therein, a movable cam; said assembly comprising a bore in said casing, a flexible diaphragm disposed in said bore, said bore below said diaphragm having a wall forming a fuel cavity shaped to permit deflection of said diaphragm, said casing above said diaphragm being adapted to be provided with a predetermined amount of hydraulic fluid, a barrel member fixed in said bore above said diaphragm and having a cylindrical barrel bore therein, saidbarrel member having a port to permit said by draulic fluid to flow, into said barrel bore,- said barrel bore communicating with the first named bore above said diaphragm, a. plunger having an end mounted for reciprocation in said barrel bore, the other end of said plunger being actuated by the cam whereby the plunger is reciprocated by said cam, means operable to cause the plunger to selectably variably control said port to vary the amount of hydraulic fluid disposed between saidplunger and diaphragm, and. consequently the amount, of, deflectionof said diaphragm assaidplunger moves toward said diaphragm, a fuel inlet communicating with said: ,fuel cavity, an; inletvalve between said fuel inletv and: cavity,v an

outlet from said cavity, and an outlet valve between said cavity and outlet. i V

14. In a pump, the combination of'a casing having an upper housing and a depending housing, a rotatable cam shaft in said upper housing, a cam operable for a portion of the rotation of said shaft, a bell crank pivoted in said upper housing adjacent said cam and adapted to be oscillated thereby, said bell crank being operable a predetermined amount by said cam for a predetermined time, said depending housing having a cylindrical bore therein, a flexible diaphragm disposed in said bore, a stop member-disposed above and fixing said diaphragm in said bore, said stop member having a passage connecting the bore above the stop member to the'bore'between the stop member and diaphragm, .a-piston mounted for reciprocation in said bore above the stop member, said casing having a passage c'o'nnecting the bore above and below the piston, said piston being adapted to close communication between the bore and passage at a predetermined point in its travel, a connection between: the bell crank and piston whereby the bell crank is adapted to raise the piston its maximum distance from the diaphragm by operation of said bell crank by said cam, resilient means for moving said piston toward said diaphragm when said bell crank is free from operation by said cam, said lower housing having a wall below the diaphragm forming a fuel cavity adapted to be filled when the diaphragm causes vacuum conditions in said cavity by returning from deflected position, an inlet to said cavity, an inlet valve between said inlet and cavity, an outlet from said cavity, and

an outlet valve between said cavity and outlet.

15. In a pump, the combination of a casing having housing portions, a rotatable cam shaft in one of said housing portions, a cam operable for a portion of the rotation of said shaft, a bell crank pivoted in said first named housing portion adjacent said cam and adapted to be oscillated thereby, said other housing portion having a cylindrical bore therein, a flexible diaphragm disposed in said bore, a piston mounted for reciprocation in said bore on one side'of said dia-.

phragm, said casing having a passage connecting the bore above and'below the piston, said piston being adapted to close communication between the bore and passage at a predetermined point in its travel, said casing being adapted to have a predetermined amount of hydraulic fluid therein on said one side of said diaphragm, a connection between the bell crank and piston whereby the bell crank is adapted to raise the piston itsimaximum distance from the diaphragm by operation of the cam shaft on said bell crank thereby permitting a predetermined amount of hydraulic fluid to be'disposed between said piston and dia phragm, resilient means for moving said piston toward said diaphragm when said bell crank is free from operation by said cam to thereby cause said hydraulic fluid to deflect said diaphragm, said other housing portion having a wall disposed on the other side of said diaphragm forming a fuel cavity adapted to be filled on the suction stroke when the diaphragm returns from its deflected position, an inlet to said cavity, an inlet valve between said inlet and cavity, an outlet from said cavity, and an outlet valve between said cavity and outlet, the amount of fuel dispensed from the cavity determining the stroke of the piston.

16. In a pump, the combination of a casing having housings. a rotatable cam shaft in one of said housings, a cam operable for a portion" of the rotation of said shaft, a bell crank pivoted in said first named housing adjacent said cam and adapted to be oscillated thereby, said other housing having a cylindrical bore therein, a flexible diaphragm disposed in said bore, a piston mounted for reciprocation in said bore above said dia phragm, said casing having a passage connecting the bore above and below the piston, said piston being adapted to close communication between the bore andpassage at a predetermined point in its travel, said casing being adapted to have a predetermined amount of hydraulic fluid therein above said diaphragm, a loose connection between the bell crank and piston whereby the bell crank is adapted to raise the piston its maximum distance from the diaphragm by operation of the cam on said bell crank, the bell crank returning to its a position where the piston has completed its stroke independently of the piston, resilient means for moving said piston toward said diaphragm when said bell crank is free from operation by said cam to thereby cause said hydraulic fluid to deflect said diaphragm, said lower housing having a wall below the diaphragm forming a fuelcavity adapted to be filled when the diaphragm causes vacuum conditions in said cavity by returning from deflected position, an inlet to said cavity, an inlet valve between said inlet and cavity, an outlet from said cavity, and an outlet valve between said cavity and outlet, the amount of fuel dispensed from the cavity determining the stroke of the piston.

17. In a pump, the combination of a casing having housings, a rotatable cam shaft in-one of said housings, cams operable for a portion of the rotation of said shaft, said cams being set in overlapping relation to each other whereby when one cam is operative the othercam is inoperative, a bell crank pivoted in said first named housing adjacent each of said cams and adapted to be operated by the respective cams, said other housing having cylindrical bores therein, a flexible diaphragm disposed in each of said bores, a piston mounted for reciprocation in each of said bores above the diaphragms disposed therein, said casing having a passage connecting each bore above and below the piston therein, each piston being adapted to close communication between its bore and the associated passage at a predetermined point in the travel of the piston, said casing being adapted to have a predetermined amount of hydraulic fluid therein above said diaphragms, a loose connection between the bell cranks and the associated piston whereby each bell crank is adapted vto raise its piston the maximum travel thereon from the associated diaphragm by operation of the associated cam on said bell crank, each bell crank returning to its position where the associated piston has completed its stroke independently of its piston, resilient means for moving each piston toward its diaphragm when its bell crank is free from operation by its camto thereby cause said hydraulic fluid to deflect said diaphragms, said lower housing having a wall below each diaphragm forming a fuel cavity adapted to be fllled when the diaphragms cause vacuum conditions in said cavities by returning from deflected position, an inlet to each cavity, an inlet valve between each inlet and cavity, an outlet from each cavity, and an outlet valve between each cavity and outlet, the amount of fuel dispensed from each cavity dc termining the stroke of each piston. 

